#include <functional>
#include <iostream>
using task_t = std::function<void()>;

void download()
{
    std::cout << "这是一个下载的任务" << std::endl;
}
void upload()
{
    std::cout << "这是一个上传的任务" << std::endl;
}
class Task
{
public:
    int getX(){return _x;}
    int getY(){return _y;}
    Task(int x,int y):_x(x),_y(y)
    {}
    void Execute(){_result = _x + _y;}
    int result(){return _result;}
    ~Task(){}
private:
    int _x;
    int _y;
    int _result;
};